The present invention relates to a wire harness slack absorbing apparatus for wiring a wire harness between a main body and a moving body so that the wire harness has at least slack needed for moving the moving body.
For example, in the case of a wire harness wired in a steering column, it is necessary for responding to operations of a tilting mechanism and a telescopic mechanism of the steering column that the wire harness is enabled to absorb the expansion and contraction of the wire harness, which are caused by operations of the mechanisms. A conventional wire harness slack absorbing apparatus provided against such a background, as illustrated in FIG. 7, is known as an apparatus having the function of absorbing the expansion and contraction of the wire harness (that is, absorbing slack in the wire harness).
As shown in FIG. 7, the wire harness slack absorbing apparatus 1 is configured in such a way as to comprise a harness case 2 and a harness cover 3. The harness case 2 and the harness cover 3 are adapted so that a slack portion 6 in a middle part of the wire harness 5 drawn out of a steering 4 can be accommodated therein in a state in which the slack portion 6 is bent in such away as to have an annular shape in a plan view. In this figure, reference numeral 7 designates a slack-portion accommodating part 7 for accommodating the slack portion 6. Reference numeral 8 denotes an outlet for the slack portion 6. Reference numeral 9 designates a rigid wire portion, which a rigid cylinder 10 is provided along and fixed to.
Meanwhile, the conventional apparatus has a problem that when the steering 4 is adjusted, the slack portion 6 is drawn out of the outlet 8 and at that time, an intersection part 11 of the slack portion 6 illustrated in FIGS. 8A and 8B rubs itself to thereby lower the durability of the wire harness 5. Moreover, the conventional apparatus has another problem that when the slack portion 6 having been drawn out of the outlet 8 is drawn into the slack-portion accommodating part 7, the intersection part 11 is caught therein and thus, the wire harness cannot be smoothly drawn thereinto.
Furthermore, reference numeral 12 denotes a fixed-end-side part of the slack portion 6. The conventional apparatus has other problems that members (not shown), such as tapes, bands, and clips, are needed for fixing the part 12 to the harness case 2 or the harness cover 3, and that thus, increase in the number of components and in the number of man-hours occurs and affects the cost of the apparatus.
The invention is accomplished in view of the aforementioned circumstances. Accordingly, an object of the invention is to provide a wire harness slack absorbing apparatus, which is enabled to enhance the durability thereof and to achieve smooth drawing-in of a wire harness and reduction in the cost thereof.
In order to solve the aforesaid object, the invention is characterized by having the following arrangement.
(1) A wire harness slack absorbing apparatus for wiring a wire harness between a main body and a moving body movably mounted on the main body so as to have at least a slack portion needed when the moving body is moved, the wire harness slack absorbing apparatus comprising:
a slack-portion accommodating part for accommodating the slack portion which is bent so as to have an annular shape in a plan view so that a diameter of the annular shape is freely increased and decreased; and
a contact restraining part which is provided in the slack-portion accommodating part and includes an end portion which comes in contact with the slack portion to provide a distance between segments of an intersection part of the slack portion which is bent into the annular shape.
(2) The wire harness slack absorbing apparatus according to (1), wherein the slack portion is interposed between the end portion of the contact restraining part and an inner surface of a wall of the slack-portion accommodating part so as to hold the slack portion.
(3) The wire harness slack absorbing apparatus according to (1), wherein the contact restraining part has elasticity.
(4) The wire harness slack absorbing apparatus according to (1), wherein the end portion of the contact restraining part has a groove for preventing the slack portion from slipping therefrom.
(5) The wire harness slack absorbing apparatus according to (1), wherein the contact restraining part has a slope provided between the end portion and a base portion thereof opposite to the end portion.
(6) The wire harness slack absorbing apparatus according to (1), wherein the distance is equal to or more than a diameter of the wire harness.